This invention relates to relays. In particular, this invention relates to small, electrostatically operated relays that may be formed using integrated circuit fabrication techniques.
In its simplest form, an electrical relay is a pair of contacts that are brought together by an electrically driven actuator. The most common example of an electrical relay is the electromagnetic solenoid driven relay. In this pedestrian type of device, an electromagnetic solenoid is energized by an external power source creating a magnetic field that causes a movable armature to move, closing contacts on the armature and the fixed stator.
Most prior art electromagnetic relays are physically large, consume large amounts of power, and are difficult to manufacture in an integrated manner. They are impractical for low cost, physically small, and energy efficient applications.
It is well known that at close separation distances, electrostatic forces may be used to effectuate closure of the relay contacts. It would be an improvement over prior art electromagnetic relays to have a very small relay with contact separation distances close enough to permit electrostatic closure of the armature and the stator.
Previous attempts at this type of device have concentrated on using piezoelectric actuators to move the electrodes. These structures never worked well, primarily because the moving contact was always very sensitive to vibration and shock. Furthermore, small, effective piezoelectric actuators are difficult to manufacture. A small, integrable, electrostaticically driven relay would be an improvement over the prior art. Such a structure might be used to switch small signals and may be used to fabricate a switched capacitor.